Nearest Unit With One-Way Streets and a Closure
An incident is reported at the intersection of 39th Street and 5th Avenue. The grid: numbered streets run east-west and increase northward (34th, 35th ... 42nd). Avenues run north-south and increase eastward (7th, 6th, 5th). 5th Avenue is one-way southbound; 6th Avenue is one-way northbound; 7th Avenue is two-way. 39th Street is two-way. Unit 12 is at 34th Street and 7th Avenue. Unit 15 is at 42nd Street and 5th Avenue. A construction closure on 5th Avenue north of 42nd Street does not affect travel between 42nd and 39th. A caller says the incident is 'right outside the pharmacy on 39th, near 5th,' but gives no exact address. The dispatcher must assign the nearest available unit and give a route that respects one-way streets. Assume street blocks and avenue blocks take about the same travel time, and units can turn only at intersections.
1. Determine which unit is closer and give a legal route for each; show block counts.
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Unit 15
From 42nd and 5th to 39th and 5th: travel south on 5th Avenue. Because 5th is one-way southbound, this is legal. Count: 42nd to 39th = 3 street blocks. Total = 3 blocks.
Unit 12
From 34th and 7th to 39th and 5th: travel north on 7th Avenue to 39th (5 street blocks), then east on 39th Street to 5th (2 avenue blocks). 7th is two-way and 39th is two-way, so this is legal. Total = 7 blocks.
Conclusion
Unit 15 is closer by block count: 3 versus 7. Assign Unit 15 on the direct southbound route on 5th Avenue.
2. What follow-up question would you ask the caller to confirm the exact location, and why?
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I would ask: 'What is the nearest cross street or house number on 39th Street, and which corner of 5th Avenue is the pharmacy on - northwest, northeast, southwest, or southeast?' I would also ask for the pharmacy name or street number.
Why: '39th and 5th, outside the pharmacy' identifies an intersection, not a side of the street or a specific address. The pharmacy could be on any corner, and the unit's approach may differ. A cross street or house number confirms the block and helps avoid sending the unit to the wrong side of a wide intersection. If the caller cannot answer, I would keep the unit responding to the intersection and advise the caller to stay on the line.
3. If Unit 15 is delayed by a garbage truck on 5th Avenue, how does that change your assignment and route?
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If the truck blocks 5th between 42nd and 39th, Unit 15 cannot use the direct 3-block route. A legal alternate for Unit 15 is: west on 42nd to 7th (1 avenue block), south on 7th to 39th (3 street blocks), then east on 39th to 5th (2 avenue blocks) = 6 blocks. Unit 12 remains at 7 blocks by its original route. So Unit 15 is still slightly shorter by block count, but the delay matters more than the count if the truck is not moving.
I would ask Unit 15 whether it can clear the delay, and if not, assign Unit 12 immediately. I would not send Unit 15 the wrong way on 5th or assume it can use 6th southbound, because 6th is one-way northbound.